MEMPHIS, Tenn. — Memphis police have confirmed that a body discovered in a ditch this weekend is that of a 7-week-old baby who went missing more than five weeks ago, and the infant's mother has been charged with first-degree murder.

Memphis police said Monday that the physical description and clothing on the body discovered Sunday in Millington, about a half-hour north of Memphis, matched that of Aniston Walker, who was reported missing Jan. 9.

The baby's mother, Andrea Walker, told police that Aniston disappeared after she left the baby at home with her 3-year-old child while taking her 5-year-old child to school.

Walker earlier pleaded not guilty to charges of aggravated child abuse or neglect and had been free on $250,000 bond.